A new sunrise ... the first Sunday edition of the Sun. Photograph: Miguel Medina/AFP/Getty Images

Rupert Murdoch's Sun on Sunday is set to report sales of more than 3m copies on its launch weekend, with the Sunday Mirror and the People suffering the most from the new title's arrival, while Richard Desmond's Star on Sunday was more resilient.

Early figures from wholesalers and retailers indicate that the Sunday edition of the Sun, which launched at a cut-price 50p backed by a multimillion-pound marketing push, is on track to surpass the 3m sales mark – while sales of its rivals tumbled by 15% to 30%.

If the trend indicated by the early data proves to be correct – newspaper publishers will have a pretty accurate sales picture by later this afternoon – Murdoch will have achieved his aim of returning to the position of market leader on Sunday. When the News of the World was closed last July it was selling about 2.66m copies a week.

The same information indicates that the biggest loser over the weekend will be Trinity Mirror, owner of the Sunday Mirror and the People, which had been the biggest beneficiary after the closure of News of the World.

Early estimates indicate that the People could be down as much as 30% week-on-week to a circulation of about 560,000; while the Sunday Mirror is looking to be down by about a quarter to approximately 1.3m. But both levels are still above the amounts the titles sold before the closure of the News of the World last July – which were 474,000 and 1.09m respectively.

The Sunday Mirror was cut from £1 to 50p in the Carlton (London), Meridian (south coast) and Central (Midlands) regions. Stablemate the People was cut from £1 to 50p in the same regions.

Richard Desmond's Daily Star Sunday, which was cut by 50% to 50p nationally, is on track for a more modest sales decline of the order of 15% to about 550,000. That would leave it almost a quarter of a million ahead of its pre-News of the World closure level, which was 306,000. The Sunday Express looks to be down about 10% to about 520,000, compared with a circulation of 538,000 before the News of the World closed.

The Mail on Sunday, which maintained its cover price at £1.50, is thought to be on track to report sales up slightly by between 1% and 2%.

The MoS, which ran a major ad campaign over the weekend, cut its price last summer to lure former NoW readers but lost financially when it failed to hold on to temporary sales gains.

Rupert Murdoch took to Twitter on Sunday night when the first feedback started to emerge from retailers. "Reports early, but new Sun edition sold 3m!" he said on his official Twitter feed @rupertmurdoch.

• To contact the MediaGuardian news desk email editor@mediatheguardian.com or phone 020 3353 3857. For all other inquiries please call the main Guardian switchboard on 020 3353 2000. If you are writing a comment for publication, please mark clearly "for publication".

• To get the latest media news to your desktop or mobile, follow MediaGuardian on Twitter and Facebook.